At least 359 migrants died when the boat, travelling from Libya, capsized.

Most were from Eritrea and Somalia.

Soldiers carry one of the victims of the 2013 sinking (Image: AFP)

British spies working for GCHQ and officers from the NCA helped track the mastermind after he left Libya to orchestrate passage for “tens of thousands of migrants from Libya”.

GCHQ assisted the NCA in trawling through chatter, while the agency used its “international network” to set up a trap with Sudanese authorities

He was extradited to Italy on Tuesday to face multiple charges of being the organiser of a transnational criminal conspiracy aimed at smuggling human beings from Africa to Italy, and on to northern Europe and the UK.

Other charges include the smuggling of migrants relating to numerous arrivals of boats in Sicily, with aggravating circumstances of the number of smuggled people, inhuman treatment and risk to the life of migrants.

He earned the nickname “The General” because he styled himself on former Libyan dictator Muammar Gaddafi .

His gangster network - dubbed “the Sopranos of Libya” - charges up to £1,500 a time for the risky Mediterranean passage to the coast of Italy.

Medhanie styled himself after Colonel Gaddafi

Sources have revealed details of how Medhanie was arrested in a dawn raid on a ramshackle building on May 24.

One source said: “Medhanie was tracked from the moment he left Libya some months ago. He had already been traced on numerous wire taps, negotiating with other people smugglers and Islamic State terrorists, planning different routes and modes of transport for thousands of migrants to get into Europe.

“It is believed he was on his way to make a deposit of several millions of dollars in protection money to Islamic State warlords in Sudan.

“The destination had been chosen as a neutral ground with a network of safe houses in the country but Medhanie was already being tracked by several European security services and by satellite.”

Italian prosecutors have also revealed Medhanie was recorded on mobile phone taps in 2013 laughing about the fatal overloading of migrant ships when 359 migrants drowned off the Lampedusa in 2013.

They recorded Medhanie bragging about bribing guards in detention centres in Libya to hand over migrants to him.

Medhanie is thought to have been heading to pay money to ISIS warlords (Image: Getty)

The gang then held them to ransom, raping and torturing them until their relatives would pay up for the next leg of their journey.

In one intercepted conversation he could be heard laughing about the fatal overloading of migrant ships.

In other recordings he discussed organising journeys across the Mediterranean and co-ordinating smuggling gangs.

Operation Glauco, a probe set up by the Italian authorities in the wake of the Lampedusa tragedy, was assisted by NCA officers from the UK Immigration Crime Taskforce in tracking down the kingpin to an address in the El Diem area of Khartoum.

One source has revealed the plans, intercepted on wire taps by British agents were on an “unprecedented scale”.

Mr Dowdall added: “Medhanie is a prolific people-smuggler and has absolute disregard for human life.

“Although he was operating thousands of miles away, his criminal activity was impacting the UK.

“Medhanie no doubt thought he was beyond the reach of European justice but we were able to support the Italians by tracking him down to Sudan.”